Train-signaling apparatus



(No Model.) 2 SheetsSheet 1.

H. R. MASON. TRAIN SIGNALING APPARATUS.

No. 450,335. Patented Apr. 14,1891.

(No Model.)

2 Sheets-Sheet 2. H.- R. 'MASQN. TRAIN SIGNALING APPARATUS-.

Patented Apr. 14, 1891.

NITED STATES PATENT Fries,

HARRY R. MASON, OF CHICAGO, ILLINOIS.

TRAIN-SIGNALING APPARATUS.

SPECIFICATION forming part of Letters Patent No. 450,335, dated April 14, 1891.

Application filed March 11, 1891. Serial No. 384,854. (No model.)

To all whom it may concern.-

Be it known thatI, HARRY R. MASON, acitizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a new and useful Improvement in Train-Signaling Apparatus, of which the following is a specification.

My invention relates to improvements in train-signaling apparatus in which a signal upon or near the engine cab is actuated by limited reductions of the air-pressure in the main train-pipe of the air-brake system,which reductions of pressure may be effected by the opening of a conductors signalingvalve located upon a car of the train and communicating with the main train-pipe.

The particular signaling system to which my improvement relates is shown and described by me in separate applications for Letters Patent of the United States, one bearing Serial No. 373,360, filed December 2, 1890, and another bearing Serial No. 380,708, filed February 9, 1891.

My object now is to provide for changes in the construction of certain features described more particularly in my application, Serial No. 330,708, with the view of better adapting them to the purposes for which they are required.

Generally stated, the apparatus and operation thereof, described in my application, Serial No. 380,708, is as follows: The system involves the use of the main air-reservoir and its pump for generating and storing the air-pressure, the train-pipe or brake-pipe which conveys the air-pressure to the triple valve, auxiliary reservoirs and brake-cylinderson the cars of the train, an engineers valve for regulating the supply of pressure to and its ex haust from the train-pipe, a signal-valve upon the engine or tender communicating directly with the train-pipe, a supplemental air chamber or reservoir communicating with the train-pipe through the signal-valve, a vent or servicestop passage or pipe extending from the service-stop inlet-port of the engineers valve and communicating with the train-pipe through the signal-valve, a movable diaphragm in the signal-valve, which only partly closes communication of the supplemental reservoir and service-stop passage with the train-pipe and causes the signal to is capable of producing only a limited reduction of pressure in the train-pipe, the reduction being too slight to move the brakes, but

sufficient to cause movementof the diaphragm in the signal-valve and thus actuate the signal. As the train-pipe is charged with pressure from the main reservoir, the supplemental reservoir is filled from the train-pipe through the signal-valve until the pressures exerted against opposite sides of the signal-valve diaphragm are equal. As before stated, the diaphragm does not entirely shut oif the comm unication through the signal-valve, and a passage, always open, permits the return of air from the supplemental reservoir to the trainpipe to a slight degree,limited by the smallness of the passage. When a conductors signalingvalve is opened, the limited venting of the train-pipe thus effected will reduce the pressure on the train-pipe side of the signal-valve diaphragm and cause the excessive pressure from the supplemental reservoir to move the diaphragm from its normal position and actuate the signal before the excess of pressure can be reduced by the retrogression of the air to the train-pipe through the small open passage referred to above, the diaphragm being returned when the pressure, by escaping to the train-pipe and signal, is reduced in the supplemental reservoir to or substantially to that in the train pipe. Any reduction of pressure, due to ordinary leakage in the system, will be so slight that whenever it causes the pressure in the supplemental reservoir to exceed that in the train-pipe an equilibrium of pressure between the two may be re-established through the small open passage in the signal-valve without moving the diaphragm. When the engineers valve is turned to service-stop, whereby the service-stop passage is opened to the outside air, thepressure in the supplemental reservoir is reduced by passing into the service-stop passage, and the pressure in the train-pipe passes through the small open passage in the signal-valve to the service-stop passage, whereby the desired slow application of the brakes is effected. Thereafter to release the brakes the en "ineers valve is turned to release position, wherein pressure is allowed to pass from the main reservoir to the train-pipe and, as before stated, to the supplemental reservoir to release the brakes, and when the main-reservoir pressure has been established throughout the system the engineers valve is usually turned to running position.

It has been foundin the practice of my invention that with the mechanism described and shown in my application, Serial No. 380,708, the turning of the engineers valve from release to running position is apt to have the effect of operating the signal. This effect, though of minor importance, it is desirable to overcome, and one of my objects in the present connection is to afford a slight change in the construction of the engineers valve whereby such an effect may be avoided.

' Another object is to afford a change in the construction of the signal-valve, whereby the passage of air-pressure from the train-pipe to the supplemental reservoir and service-stop passage may be more rapid than was possible with the construction shown and described in my application, Serial No. 380,708, without increasing the size of the small open passage for the retrogressive pressure from the supplemental reservoir to the train-pipe.

In the drawings, Figure l is a plan view of the engineers valve, the upper movable part of the valve being removed to expose the valve-seat; Fig. 2, a bottom plan view of the upper movable part or regulating-valve, which seats and turns upon the valve-face shown in Fig. 1; and Fig. 3, a central vertical section of the signal-valve.

The engineers valve A contains the valve face or seat t, upon which is fitted a rotary regulating-valve s. Extending through the shell of the valve A into the chamber above the regulating-valve s is a passage which is cored through the part r of the shell and communicates with the main air-reservoir.

In the valve-seat t are a release-port 0, which communicates with the train-pipe; a running-position or service-feed port 1a, which communicates through a supplemental valvechamber in the shell A with the trainpipe; an emergency port it and a servicestop outlet-port m, both of which lead to the outside air; a service-stop inlet-port Z, and a segmental recess or cavity 1:. The regulatin g-valvesis provided with a passage hthrough it, and in its lower face are two recesses or cavities g and g, communicating with each other through a passage g which is cored in the valve, and a small recess or cavity m.

D is the signal-valve, comprising a shell,

which may, as shown, connect with the trainpipe 0 at opposite sides of its upper part, and affords a piston-chamber D and a small auxiliary valve-chamber 6.

through the center of which is an opening E,

. ber e is never entirely closed.

The chamber D is closed at its lower end by a screw-cap D from which the pipe E extends to the signal, which is preferably a whistle.

F is a pipe extending from the lower part of the chamber D to the supplemental reservoir, (not shown) and a branch pipe Z extends from the pipe F to the engineers valve, where it communicates through a passage in that valve with the service-stop inlet-port Z. The valve-chamber e communicates through a passage 9 with the train-pipe and through a passage e with the lower part of the chamber D. In the chamber 6 is a check-valve a which seats in the direction of the train-pipe, and is held in its place bya spring (2 of slight resistance. Through the valve e is a small passage f which operates to afford communication between the chamber D and trainpipe when the valve 6 is seated, whereby the passage between the chamber D and train-pipe through the auxiliary valve-cham- The passage f serves the function performed by the small open passage referred to in the first part of this specification as a feature of my former construction. The exact location of the passage f is not material, as a passage in any desired position which will serve to maintain an open but properly limited communication between the train-pipe and supplemental reservoir is all that is required.

G is a piston or movable diaphragm in the chamber D upon a stem G, which passes through a guide f on the cap D The piston G fits closely against a stationary bushing don the Wall of the chamber D, to prevent leakage at its circumference, and it moves without material friction. Housed in a screw-cap c at the top of the chamber D and movable longitudinally in a socket therein is a graduating-piston 0, held normally at the lowest limit of its play by a graduatingspring 0 The piston c is directly in line with the stem G. At its lower end the stem G seats normally upon the cap D over the opening E, which it thus operates to close effectively. In the side of the chamber D is a recess or groove f which exceeds somewhat in its vertical extent the thickness of the piston G. The lower end of the groove f is at about the plane of the upper side of the piston, and the distance apart of the lower end of the graduating-piston c and the upper end of the stem G, when the latter is in its lowest or normal position, is somewhat less than the length of the groove f. Extending downward from the valve-shell at the top of the chamber D around the graduating-piston is an annular projection 0 which limits the descent of the graduating-piston and the rise of the piston G.

In operation, as the train-pipe is charged with pressure from the main reservoir, pressure passes down through the passage 6, opens the check-valve e and passes through the passage e to the chamber D below the piston G, and thence-through the pipe F, filling the supplemental reservoir and pipe Z, the

opening of the check-valve e permitting the air to pass much more rapidly than were the opening f alone depended upon. The pressure upon the upper side of the piston Gholds the stem G against its seat at the opening E, whereby no air can escape into the pipe E. When the pressure in the lower part of the chamber D is equal or substantially equal to that in the train-pipe, the check-valve e closes. Any slight variations in pressure on opposite sides of the piston G, such as might be occasioned by ordinary leakage in the system, would be quickly overcome through the passage f so that the piston Gwould not be moved. When a conductors' signaling-valve upon a car of the train is opened, the limited reduction of pressure thus suddenly efiected in the train-pipe will cause the now excessive pressure uii'der the piston G to lift the latter until the stem G strikes the graduatingpiston c. The escape of pressure through the groove f around the piston and through the passage f and to the signal quickly equalizes the pressure on opposite sides of the piston G to an extent which will cause the latter to rebound or drop almost instantly to the normal position. In the meantime the signal will have been actuated by the escape of air through the pipe E. In the event of a sudden evacuation of the pressure in the train-pipe, such as would happen should a breakage occur, a coupling part or a conductors break-valve be opened, the sudden great reduction of pressure on the train-pipe side of the piston G would cause the piston to be driven up against the gradu ating-piston, compress the latter and seat against the stop 0 thereby closing the passage and preventing the air from the supplemental reservoir from entering the trainpipe through the passage f to delay the application of the brakes. The signal in such an event will be actuated until an equilibrium is again established on opposite sides of the piston G, or the supplemental reservoir is exhausted, and the engineer will' thus be quickly apprised of an emergency. Of course the same would happen when the engineers valve is turned to emergency stop. \Vhen the engineers valve is turned to service stop, whereby the pipe Z is opened to the outside air, the pressure in the supplemental reservoir and chamber D under the piston G will be reduced and pressure from the train-pipe will open the check-valve e and pass in to fill its place until the train-pipe is vented sufficiently to apply the brakes with the desired force and the service-stop is closed. when the service-stop is closed, the supplemental reservoir will prevent such a rebound of pressure in the train-pipe as to effect the release of brakes. To release the brakes the engineers valve is turned to the release position, causing the train-pipe and supplemental reservoir to be charged with pressure from the main reservoir, and when the proper pressure is established the engineers valve is turned to running position. In the lastnamed movement of the engineers valve a sudden checking of the pressure from the main reservoir to the train-pipe and supplemental reservoir is effected, which is apt to produce a rebound of pressure from the latter sufficient to move the piston G from its normal position and actuate the signal. To prevent such an occurrence I provide in the lower face of the regulating-valve s a recess m which is in a position to register momentarily with the service-stop inlet and outlet ports m Z, as the valve is being turned from release to running position and cause a limited amount of pressure to escape from the supplemental reservoir, which, by reducing the pressure therein for the instant below that in the train-pipe,will overcome anytendency of the pressure in the supplemental reservoir to rebound, as described.

While I have described the preferred construction which I employ in carrying out my invention in detail, I desire it to be understood that my invention is not limited to details of construction; but

What I claim as new, and desire to secure by Letters Patent, is-

1. In an air-brake and signaling mechanism for railway-trains, the combination, with the train-pipe, signal, and signal-actuating mechanism, of a chamber having constant communication with the train-pipe, and a valve located between the train-pipe and chamber and arranged to permit a more rapid passage of airfrom the train-pipe to the chamber than in the reverse direction, substantially as described.

2. In an air-brake system for railway-trains, the combination, with the main air-reservoir, engineers valve, and train-pipe, of a supplemental air-chamber communicating with the train-pipe to be supplied with pressure therefrom, a signal-operating diaphragm between the said supplemental chamber and trainpipe partly closing communication between the train-pipe and supplemental chamber, an open passage, and valve mechanism between the train-pipe and supplemental chamber, whereby the retrogression of air from the supplemental chamber to the train-pipe is rendered slower than the passage of air from the train-pipe to the supplemental chamber, substantially as described.

3. In an air-brake system for railway-trains, the combination, with the main air-reservoir, engineers valve, and train-pipe, of a supplemental air-chamber communicating with the train-pipe to be supplied with pressure therefrom, a signal-operating diaphragm between the supplemental chamber and train-pipe only partly closing communication between the train-pipe and supplemental chamber, whereby an open passage is maintained between the two and to be moved from its normal position by pressure against it from the supple- IIO ITS

mental chamber in excess of the pressure in the train-pipe, and a valve in the said open passage operating substantially as described.

4:. In an air-brake and signaling mechanism for railway-trains, the combination, with the train-pipe, of a supplemental chamber communicating With the train-pipe to be supplied With pressure therefrom, avalve device located between the train-pipe and supplemental chamber having an outlet-port to the signal, a diaphragm in the valve device normally closing said outlet-port and to be moved from its seat by pressure from the supple mental chamber in excess of the pressure in the train-pipe, a yielding stop in the path of 1 the diaphragm, and a passage from the supplemental chamber to the train-pipe normally 

